Centerless grinder



Sept. 16, 1958 A. w. TODD ETAL 2,851,828

CENTERLESS GRINDER Filed Nov. 28, 1956 s Sheets-Sheet 1 x I [ifuvvsurons AL EXANDEI? w r000 w RICHARD M. ANDERSON I RUSSELL L. FL EM/NGATTORNEYS Sept. 16, 1958 3 Sheets-Sheet 2 Filed Nov. 28, 1956 INVENTORSALEXANDER W TODD RICHARD MANDERSON 6 m M M m LaT A u? M UM Sept. 16,1958 A. w. TODD ETAL 2,851,828

CENTERLESS GRINDER Filed Nov. 28, 1956 s Sheets-Sheet :5

IN VE N TORS ALEXANDER W TODD RICHARD MANDE'RSON RUSSELL L. FLEMING ATTORNEVS United States Patent CENTERLESS GRINDER Alexander W. Todd,Springfield, and Richard M. Anderson, East Longmeadow, Mass., andRussell L. Fleming, Crescent Lake, Comm, assignors, by mesneassignments, to Van Norman Industries, Inc., Springfield, Mass., acorporation of Massachusetts Application November 28, 1956, Serial No.624,918

4 Claims. (Cl. 51-403) This invention relates to a centerless grinderand,

more particularly, to an improved regulating wheel asv the attacheddrawings showing a presently preferred em- 7 bodiment of the inventionand in which drawings Fig. 1 is a front view of a centerless grinderconstructed in accordance with this invention;

Fig.2 is an enlarged horizontal sectional view through the regulatingwheel assembly taken as indicated by the line 2-2 of Fig. 1; and

Fig. 3 is a further enlarged vertical sectional view of the regulatingwheel assembly taken as indicated by the line 3-3 of Fig. 1.

As will be readily understood from Fig. 1, a centerless grinderincorporating the features of the present invention is similar in manyrespects to conventional centerless grinders. That is, the grinderincludes a conventional bed 10 upon which a grinding wheel assembly 12and regulating wheel assembly 14 are mounted. The grindingwheel-assembly 12 includes an abrasive wheel 16 mounted on a spindlewhich is rotatably supported in a housing (not, shown) and covered by aguard 18. The entire grinding wheel assembly 12 is quite conventionaland only so much of it is shown as is necessary to describe therelationship of the grinding wheel 16 to the regulating wheel assembly14, and it is deemed unnecessary to show or to describe the grindingwheel drive structure, the wheel dressing apparatus or the coolantsystem for the grinding wheel.

In accordance with conventional practice, the grinding wheel assembly 12is fixedly or adjustably mounted on the bed 10 so that the grindingwheel 16 is disposed in generally opposed relationship to a regulatingor control wheel 20 forming a part of the regulating wheel assembly 14,and in further accord with conventional practice, a work rest 22 isadjustably mounted on the bed 10 between the said grinding andregulating wheels. A worksupporting blade 14 is secured to the work restto support the work (not shown) for engagement by the grinding wheel andthe regulating wheel. The work rest can be moved on the bedindependently of or with the regulating wheel assembly which will now bedescribed.

The regulating wheel assembly 14 includes a wheel housing 26 which isadjustably supported on a main housing 28, the main housing beingslidably mounted on the bed 10. The upper portion of the main housing 28may be considered a gear box wherein the gears and other motiontransmitting means of the regulating wheel drive 2,851,828 PatentedSept. 16, 1958 ent invention is involved principally in the constructionand arrangement of the wheel housing 26, the upper portion of the mainhousing 28 and the elements of the regulating Wheel drive. Therefore,the lower portion of the main housing and the elements for advancing andretracting the regulating wheel, all of which are conventional, need bedescribed only generally.

As will be observed from Fig. 1 of the drawings, the lower or slideportion of the main housing 28 is movable laterally of the machine onways 30 at the top of the bed 10 whereby to advance the regulating wheel20 toward the grinding wheel 16 or to retract it therefrom. The workrest 22 is movable on the same ways and a rod 32 secured to the saidwork rest extends into the slide portion of 'the main housing 28 forselective connection with the main housing. The means for selectivelyconnecting the rod 32 with the main housing 28 comprises an elongatedbinder screw 34 (Fig. 3) which is supported in the main housing and canbe advanced to bind the lating wheel assembly and when rotated in theopposite Obviously, the said sleeves can be rotated manually or by poweroperated direction .will retract the same.

means. In the drawings, a hand operated lever 42 is shown as the meansfor rotating the sleeves to advance and retract the regulating wheelassembly in grinding operations. A handle 44 is secured to the lever 42and extends laterally toward the grinding wheel for the convenience ofan operator standing at the front of the machine. When the lever 42 isrotated forwardly and downwardly from the position shown to engage astop 46, the said sleeves are rotated to advance the regulating wheel 20a predetermined distance toward the grinding wheel 16 and, in so doing,a workpiece supported on the blade 24 is ground to a selected diameter.The advanced position of the regulating wheel is indicated by the brokenline in Fig. 1. Then, when the lever 42 is returned to the positionshown, the regulating wheel assembly is retracted, returning theregulating wheel 20 to the full line position.

In order that advance and retraction of the regulating wheel by the saidpredetermined distance will effect the grinding of a workpiece to aselected diameter, it is necessary that the advanced position of theregulating wheel assembly be accurately fixed. It is also necessary thatthe said advanced position be accurately relocated from time to time tocompensate for wear and dressing of the grinding wheel 16 and theregulating wheel 20. The means for adjusting and locating the advancedposition of the regulating wheel and its assembly also comprises athreaded sleeve or nut (not shown) which engages the lead screw shaft 38and is manually operated by a hand wheel 48 at the front of the mainhousing 28.

The main housing also includes a reservoir for the lubricant used in theregulating wheel assembly. The

reservoir itself is not shown, but there are two sight' windows 50, 50provided at the front of the main housing for checking the lubricantlevel in the reservoir, and a lubricant pump 52 operated by a handle 54is provided for circulating the lubricant through a plurality ofcontduits 56, 56. (The pump 52 and oil lines 56, 56 are shown in Fig.3).

As thus far. described, the, centerless grinder is construct'ed inaccordance with known practice. The operation' of the machine is alsoconventional. That is, a control panel 58 is provided at the front ofthe machine and contains the usual switch buttons 60, 60 for startingand the thru-feed method, it may be desirable to tilt the regu latingwheel spindle. The centerless grinder of this invention is particularlyadapted to make regulating wheel tilting a more precise but easy task,such adaptation involving an improved regulating wheel support and drivearrangement which will now be described.

The regulating wheel drive motor 62 is arranged on top of the mainhousing 28 so that its shaft projects into a speed control unitindicated generally at 64. It is believed to be unnecessary to describethe unit 64 (since it is conventional) beyond saying that it is adaptedto vary andthuscontrol the speed of an output shaft (not shown) within arelatively wide range by manipulation of a hand wheel 66. In thisinstallation, the output shaft mounts a pulley for a belt drive to theregulating wheel,. and the hand wheel 66 is turned to select aregulating wheel speed indicated at a tachometer 68 on the front of themain housing. 28.

Turning now to Fig. 2', it will be observed that the drive belt 70extends from the speed control unit 64 downwardly into the main housing28 to a pulley 72 which is keyed to one (74) of a plurality of shaftsrotatably supported and sealed in the main housing as by theanti-friction bearing units 76, 76 and the seals 78, 78. The pulleyshaft 74- extends from the right-hand end of the main housinglongitudinally thereof, terminating in a splined end 80. A; pinion 82 issecured to the splined end of the pulley shaft 74 and engages a compoundgear 84 and the pinionv 82 hasan exposed end face 86 engageable with anaxially movable clutch 88 as will be described.

The compound gear 84 is rotatably supported on a bearing stud 90 whichis secured within the main housing 28 parallel to the pulley shaft 74,and the compound gear hasa large diameter gear 92 at one end and apinion 94 at the other end. The pinion end 94 is engaged with a gear 96which is rotatably supported on a driven shaft 98. The gear 96 has anexposed face 100- which is engageable with the clutch 88 which issplined to but movable along the driven shaft 98. It willbe observedthat th'edrivensha'ft 98 and pulley shaft 74 are aligned on a laterallyextending substantially horizontal axis and:the

bearing stud 90 is parallel therewith. The faces 86 and 100 of" thepinion 82 and the gear 96, respectively, are provided with clutch teethwhich are engageable respectively with'similar teeth on the oppositeends of the clutch 88.

The aforesaid arrangement of the pinions and gears 82, 84' and 96 andthe arrangement of the clutch 88 provides variable speed motiontransmitting means between the drive motor 62 and-the driven shaft 98.That is, the aforesaid arrangement provides for a high and low speedrange selection while the speed control unit 64 provides means forselecting a more specific speed within either range. More specifically,when the clutch 88 is shifted tothe right to engage the pinion 82 on thepulley shaft 75, it provides a direct driving connection between thepulley shaft and the driven shaft 98 whereby the driven.

shaft is rotated at the speed of the pulley shaft. When theclutch isshifted to the left to engage the gear. 96 on the driven shaft 98, theconnection between the pulley" shaft and the driven-shaft is indirect,-through the compound gear 84 and the gear 96 which rotates at a speedsubstantially less than the speed of the pulley shaft.

Any clutch-shifting means may be provided which can conveniently beoperated. One such means may comprise a forwardly and rearwardly movablerack supported in the main housing 28 and operated by a handle 102 atthe front thereof, the rack engaging a pinion (not shown) secured to agenerally vertical shaft having means attached thereto and engaging theclutch 88 to shift the same axially responsive to rotation of the saidpinion and shaft.

The end of the driven shaft 98 opposite the pulley shaft is rotatablysupported on an anti-friction bearing unit 76 in a bearing drum104 andsecures a bevel pinion106 for rotating a spindle drive shaft 108 as willbe described. The bearing drum 104 is provided in accordance with thepresent invention to be rotatably supported in a suitable opening in.the end of the main housing 28 which faces the grinding wheel 16. Theaxis of rotation of-the. bear. ing drum is the lateral substantialhorizontal axis of'the driven shaft 98.

In additionto'the driven shaft 98, the bearing drum104 rotatablysupports the aforesaid spindle drive shaft 108 on anti-friction bearingunits 76, 76, the drive shaft projec'tin'g, rearwardly of the mainhousing 28 through an opening 110 which accommodates angular movementsof the said drive shaft'in a vertical plane. A sleeve 112 is splinedto'the inner end of the spindle drive shaft 108 and a bevel gear 114 iskeyed to the sleeve in engagement with the pinion 106 on themotor-driven shaft- 98. The spindle'drive shaft 108 is connected (aswill be described), by motion transmittingmeans to a spindle supporting,the

regulating wheel whereby the regulating wheel is rotated by the spindledrive shaft. Thus, the speed of rotation of the regulating wheel isdirectly related to the speed of rotation of the drive shaft 108.Accordingly, a flex ible shaft 116 can be connected between thetachometer 68 and the-spindle drive shaft 108 as best shown in Fig.

3 and-thetachometer 68 calibrated to indicate regulating.

wheel speed although connected to the spindle drive shaft.

The bearing drum 104, in addition to rotatably supporting the. drivenshaft 98 and spindle shaft 108', also provides meanswhereby theregulating wheel'spindle and the drive'shaft can be adjusted-angularlywith the regu-' lating wheel frame or housing 26 without disturbing thedrive connection to the regulating wheel and the selected speed thereof.That is, the bearing drum 104' is pref era'bly connected to theregulating wheel frame 26 as' by' screws (not shown) and thus it isarranged to rotate with the said regulating wheel frame which ispivotally adjustably secured to the main housing on the end thereofwhich faces the grinding wheel 16.

More specifically, the regulating wheel frame 26- is detachably andadjustably secured to the main housing 28 by means of a plurality ofbolts 118, 118 supported in the aforesaid end of the main housing 28 andtightened therein by a plurality of nuts 120, 120. The head ends of thebolts 118, 118 are disposed in arcuate slots 122, 122 in the regulatingwheel frame and secure the said frame in adjusted position when the nuts120, are tightened. The adjustment of the frame 26 relative to the mainhousing 28 is pivotal and about the laterally extending substantiallyhorizontal axis upon which the bearing drum 104 and the driven shaft 98rotate.

1 The regulating wheel frame or housing has a rearwardly extendingportion 124 which rotatably supports the projecting rear end of thespindle drive shaft 108 on' a suitable antifriction bearing. Theprojectingrear por tion124-of the regulating wheel frame also supports ahousing1'26 for thespindle 128 upon which the regulating wheel 20 issecured. lating wheel spindle 128 projects rearwardly similarly to thespindle drive shaft 108 and that the projectingrear' ends of the spindleand its drive shaft are connected: by.

It will be observed that the regu-- asensss motion transmitting means130 which preferably comprises a pair of pulleys and a timing belt.

It will be obvious that since the spindle drive shaft 108 is supportedby the regulating wheel frame 26 and by the bearing drum 104 and sincethe said frame and regulating wheel can be pivoted about the same axis,pivotal adjustment of the regulating wheel frame relative to the mainhousing will cause similar rotative movement of the drum relative to themain housing. Also, such pivotal or swivel movement of the regulatingwheel frame 26 and the drum 104 will cause similar adjustment of theangular disposition of the regulating wheel spindle 128 and the spindledrive shaft 108 in parallel substantially vertical planes.

In further accord with the present invention, means are provided forprecisely adjusting the swivel or pivoted position of the regulatingwheel frame 26 and the accompanying elements. Such means comprise anelongated screw 132 supported in the main housing with its head endprojecting forwardly therefrom. The screw can be arranged to directlyengage the frame 26, but in the preferred construction, it engages apost 134 which is secured to the frame and extends laterally into themain housing. The main housing is provided with a suitable opening 136to accommodate the post and limited movement thereof with the frame. Itwill be seen that by setting the screw 132 relative to the main housing28 the pivoted position of the frame 26 and the associated elements canbe easily located and fixed. When the screw is advanced into the mainhousing in engagement with the post 134, it pivots the frame so that therearwardly extending portion 124 thereof is elevated about the aforesaidlaterally extending substantially horizontal axis, When the screw 132 isretracted relative to the main housing, the weight of the overhangingrearwardly extending portion 124 of the frame and the weight of therearwardly extending portions of the spindle and spindle housing and thespindle drive shaft and the weight of the motion transmitting means andany guard therefor tends to pivot the frame so that the post 134 willengage the end of the screw 132. Therefore, it will be readilyunderstood that adjustment of the pivoted position of the frame and thepivoted position of the regulating wheel spindle can easily be effectedmerely by loosening the nuts 120, 120 on the securing bolts 118, 118 andby turning the adjusting screw 132.

Additional adjustment of the regulating wheel 20 is provided inaccordance with the present invention, this additional adjustment beingaxially of the regulating wheel spindle. That is, a spindle housing 126has a rack 138 secured thereto which is engaged by a pinion 140 which issecured to a shaft 142, the said shaft being rotatably supported in theframe 26 in a substantially vertical position. The shaft 142 projectsabove the frame 26 so that it can be manually turned to adjust thespindle housing and the spindle 128 forwardly and rearwardly along itsaxis. Movement of the spindle housing is accommodated on ways 144 asshown in Fig. 1.

From the foregoing description, it will be understood that theregulating wheel assembly for a centerless grinder provided inaccordance with the present invention features a regulating wheelsupport frame or housing which can easily and accurately be pivotedrelative to the main housing of the assembly whereby to adjust theangular disposition of the regulating wheel spindle without in any waydisturbing the drive connection to the spindle or the selected speed ofoperation thereof. Thus, the regulating wheel spindle can easily bepivoted as desired for thru-feed operation or for any other operation ofthe grinder. In addition to the foregoing, the regulating wheel assemblyprovides for adjustment forwardly and rearwardly of the regulating wheelspindle and the regulating wheel as desired for various modes ofoperation.

While the invention has been described with specific reference to thedrawings showing a presently preferred embodiment, it will be understoodthat the drawings and description are not to be construed as limiting ordefining the invention, the following claims being relied upon for thatpurpose.

The invention claimed is:

1. A regulating wheel assembly for a centerless grinder and comprising amain housing which is movable laterally in the grinding operation, adrive motor rigidly secured to the main housing, a bearing drumsupported in said main housing for pivotal movement on a lateralsubstantially horizontal axis, a shaft driven by said motor androtatably supported in the main housing on said axis and projecting intosaid bearing drum, a spindle drive shaft rotatably supported in saidbearing drum for pivotal movement therewith and projecting rearwardly ofthe drum and the main housing, motion transmitting means interconnectingthe motor driven shaft and the spindle drive shaft to effect a drivingconnection therebetween in any pivoted position of the drum, a framesecured to the main housing for pivotal adjustment on said axis androtatably supporting the rearwardly projecting end portion of thespindle drive shaft, a regulating wheel spindle rotatably supported bysaid frame, and motion transmitting means interconnecting said spindleand the spindle drive shaft, the pivotal adjustment of the frame beingeffective to adjust the spindle, the spindle drive shaft and the bearingdrum about said axis.

2. A regulating wheel assembly for a centerless grinder and comprising amain housing which is movable laterally in the grinding operation, adrive motor rigidly secured to the main housing, a bearing drumsupported in said main housing for pivotal movement on a lateralsubstantially horizontal axis, a shaft driven by said motor androtatably supported in the main housing on said axis and projecting intosaid bearing drum, a spindle drive shaft rotatably supported in saidbearing drum for pivotal movement therewith and projecting rearwardly ofthe drum and the main housing, motion transmitting means interconnectingthe motor driven shaft and the spindle drive shaft to effect a drivingconnection therebetween in any pivoted position of the drum, a framesecured to the main housing for pivotal adjustment on said axis androtatably supporting the rearwardly project ing end portion of thespindle drive shaft, a regulating wheel spindle rotatably supported bysaid frame, motion transmitting means interconnecting said spindle andthe spindle drive shaft, and a manually operable adjusting screwthreaded in said main housing and projecting rearwardly therein intoengagement with said frame below said axis whereby to adjust the pivotedposition of the frame and similarly to adjust the pivoted position ofthe spindle, the spindle drive shaft and the bearing drum.

3. A regulating wheel assembly for a centerless grinder and comprising amain housing which is movable laterally in the grinding operation, adrive motor rigidly secured to the main housing, a bearing drumsupported in said main housing for pivotal movement on a lateralsubstantially horizontal axis, a shaft driven by said motor androtatably supported in the main housing on said axis and projecting intosaid bearing drum, a spindle drive shaft rotatably supported in saidbearing drum for pivotal movement therewith and projecting rearwardly ofthe drum and the main housing, motion transmitting means interconnectingthe motor driven shaft and the spindle drive shaft to effect a drivingconnection therebetween in any pivoted position of the drum, a framesecured to the main housing for pivotal adjustment on said axis androtatably supporting the rearwardly projecting end portion of thespindle drive shaft, a spindle housing secured to said frame foradjustment forwardly and rearwardly, a regulating wheel spindlerotatably supported in the spindle housing, and motion transmittingmeans interconnecting said spindle and the spindle drive shaft, thepivotal adjustment of the frame being effective to; adjust" the:spindle; the spindle drive shaft and the:

bearing, drum about said axis;

4'. A regulating wheel assembly for a centerl'ess grinder and comprisingamain housing which is movable laterally in the grinding operation, adrive motor rigidly secured to the main housing, a bearing drumsupported in said main housing for pivotal movement on a lateralsubstantially horizontal axis, a shaft driven by said'rnotor androtatably supported in the main housing on said axis and projecting intosaid bearing drum, a spindle drive shaft rotatably supported in saidbearing drum for pivotal movement therewith and projecting rearwardly ofthe drum and the-main housing, motion transmitting means interconnectingthe motor driven shaft and thespindle drive shaft to effect a drivingconnection therebetween in 15 any pivoted position of' the drum, a framesecured to the main housing for pivotal adjustment on said axis androtatably supporting the rearwardly projectingi end portion of thespindle driveshaft, a spindle; housing secured.

to said frame for adjustment forwardly and rearwardly;.

mentwith' said framebelow said axis whereby to adjust:

the; pivoted position of the frame and similarly to adjust the pivotedposition of the spindle, the spindle driveshaft. and the. bearing.drum.v

References Cited in the fileof this patent UNITED STATES PATENTS1,985,433 Turner Dec. 25,, 19,51

FOREIGN PATENTS 562,362 Great Britain June 28, 1944'

